Posted On 06 Feb 2019
Every year farmers, their family members and employees are injured or killed in grain bin entrapments. Grain owners store grain to hedge market price fluctuations as well as to keep their harvest on schedule.
Pristine grain management is the key to preventing the need to enter a grain bin. In reality, that is an objective many farm operators cannot reasonably maintain.
The three most common ways in which people become entrapped in grain are associated with unloading.
- Flowering Grain:
During unloading, the grain bin flows downward from the top center of the bin creating a “funnel” effect that drains material and objects down to the conveyor. A loading auger at the bottom of the bin transports the grain outside. It only takes two to three seconds to become helpless in flowing grain; flowing grain acts like quick sand and can pull a worker under and cause suffocation. This hazard can happen inside a gravity wagon.
- Collapse of a Grain Bridge:
A grain bridge can form when grain on the surface is moldy or is frozen together to form a hard thick crust. When grain is unloaded from a bin with surface crust, a hollow cavity can form underneath the grain bridge. If an individual enters the grain bin and attempts to walk on the crusted surface, the additional weight can cause the crust to collapse and the individual could be partially or completely submerged instantly. The shifting grain can move the victim four or five feet from the point of entry where the victim was last seen, making it very difficult for rescuers to determine where the victim is located.
- Avalanche of a Vertical Grain Wall:
Grain in poor condition can stick and cake in large vertical columns against the grain bin wall. Workers may attempt to dislodge the grain by poling it with a stick or shovel. This can cause the wall of grain to break free, resulting in an avalanche that can completely bury workers inside the bins.
POINTS OF PREVENTION:
- Educate family members, employees and visitors to the dangers of flowing grain.
- Place warning signs and decals on all grain bin entrances and gravity wagons.
- Turn off and lock out power controls to unloading conveyors before entering a bin.
- Always use a salty harness, safety line and at least two observers during bin entry.
- Tie a permanent life line in the bin, possibly a rope with knots tied in it, so a trapped person has something to hang on to.
- Secure your grain bin areas to prevent entry by unauthorized persons.
- Teach your employees to detect whether a grain bin exists; always look for an inverted cone after unloading from a grain bin. The newly exposed grain surface should look shiny. If it does not, a bridge may have formed.
- Use a pole or other object to free the bridge from the grain bin roof hatch or from the inside ladder while tied to the ladder securely. Do not stand on the grain surface.
- Carry a long pole when entering grain bins to probe grain for cavities and stabilize the worker in case of sudden grain flow.
- Use a body harness and safety rope that is securely tied off.
- Work top to bottom of a vertical grain wall; always staying above the highest point of the wall.
- Be prepared for the entire grain wall to break free and fall at any time.
- Manage grain in storage to avoid conditions that cause spoilage and fermentation of vertical grain walls.
Grain Bin Rescue Procedures:
- Be sure the auger or loading equipment is shut off and locked.
- Contact an emergency rescue or fire department.
- Ventilate the bin with an aeration system, if one is present. Never activate the heat source.
- Avoid putting additional pressure on the victim
- Stay away from the area immediately around the victim
- Use a ladder, plywood or other material to distribute weight
- Keep unnecessary personnel out of the grain bin
- Protect first responders and other rescuers
- Attach safety lines to rescuers
- Use respiratory protection as required; dust filter masks, filter respirators or SCBA
- Construct a retaining wall when the surrounding grain slope is above the entrapped persons head.
- Use plywood, sheet metal, garbage cans with bottoms removed or heavy cardboard to keep grain from entrapped persons chest and head.
- Multiple retaining walls may be necessary.
- Remove grain from around the entrapped victim.
- Attach a harness to the entrapped victim to prevent further submission into the grain. Do not try to pull out the victim without removing the grain (hoist or block and tackle removal can cause serious injury).
- Use a vacuum conveyor or scoop to remove grain from around entrapped victim.
- Be careful when parts of the entrapped victim are not visible to avoid further injury.
- Cut holes in the grain bin wall and drain the grain.
- Do this immediately if the victim is completely submersed.
- Cut at least two holes on opposite sides of the bin; three to four holes symmetrically spaced are recommended. More holes may be needed on large bins.
- Use a “U” or “V” shaped cut.
- Make a cut 30” to 40” across between the bolt lines of a single sheet (never cut across vertical or horizontal bin sheet joints).
- Locate holes just below the feet of a partially submerged entrapped victim or as low as possible if the victim is not visible.
- You can use an air chisel, power saw, cutting torch or even the bucket of a loader tractor
- Drain the grain uniformly from two, three or four holes evenly around the grain bin.
- Provide care for the entrapped person.
- Assist the victims breathing by using oxygen or SCBA
- Maintain body temperature with saline plasma I.V. or other means
- Communicate with patient about his/her condition and rescue activities taking place.
- Plan ahead for removal of patient from the grain bin.
- Stay calm, be patient and don’t give up. There have been situations where victims have survived complete burial in grain for up to two hours.